This invention relates generally to coupler assembly for coupling a work implement to a work machine and more particularly to a coupler assembly which provides quick coupling of the work implement to the work machine through a coupler assembly with a rotating catcher and automatic latching device.
Current work machines must have the ability to utilize various implements during operation in order to complete a multitude of work tasks. Equipment used to couple the various implements to the work machine should be easy to use so that excessive physical strain on an operator may be virtually eliminated. Furthermore, the coupling equipment must be strong and reliable in order to withstand high forces incurred during operation and designed with fewer parts for a simpler, low cost design.
A design disclosed in U.S. Pat. No. 4,747,612 issued to John B. Kuhn on May 31, 1988 utilizes a coupler or hitch assembly of the latch type. Angled jaws on the coupler act together with the ramps or angled arms on the equipment secured by the coupler to forgive vertical or horizontal misalignment during the coupling operation. The assembly has an automatically engaging latch plate which is held in a closed position by a lock pin holding mechanism with a lock pin. The lock pin holding mechanism also provides frictional restraint for holding the plate in an open position. The lock pin holding mechanism allows relatively unresisted movement of the latch plate from an open to a closed position. Movement of the latch plate is also controlled by a limit tab on the coupler to prevent the lock pin from interfering with the coupler operation. Although this system utilizes a latch type coupler, it is designed and functionable in a manner which is not conducive for typical heavy industrial quick coupling. For example, the coupler assembly requires that a pair of latch plate members with various components be spaced across the width of the work machine in order to operate in coupling an implement. Further, the latch plate members are disposed at an outer surface of a mounting bracket which makes them vulnerable to greater wear and possible damage which may reduce the functionability of the coupler assembly. Even further, there is no automatic means for forcing the latch plate members to the coupling position during decoupling.
The present invention is directed to overcoming the problems as set forth above.
In an aspect of the present invention, a coupler assembly is disclosed which selectively couples a work implement with first and second coupling pins to a work machine with a structural arm and a linkage. The coupler assembly includes a pair of plates which are interconnected by a shaft to define a receiver with connecting and coupling end portions. First and second connecting pins extend continuously between the pair of plates for attachment to said respective structural arm and linkage. The connecting end portion defines a first outwardly open coupling pin receiving notch adapted for receiving said first coupling pin of the work implement. The coupling end portion defines a second outwardly open coupling pin receiving notch adapted for receiving said second pin of the work implement. A mounting opening extends through each of said pair of plates in the coupling end portion of the receiver. A cylindrical catcher has a bore therethrough and is rotational mounted between the pair of plates at the coupler end portion of the receiver. The catcher is movable between an open and closed position. The catcher has a latch notch along its length at a first location and an actuating notch along its length thereof at a second location substantially opposed to the first location. The actuating notch is proximate the second receiving notch. The actuating notch includes an open jaw and a cam surface engageable by the second coupling pin for rotating the catcher counterclockwise relative to the second receiving notch to the closed position wherein the jaw partially obstructs the second receiving notch. A resilient lock assembly is mounted on each of the pair of plates at the coupler end portion. The lock assembly has a latch member which is slidably supported within each of the mounting openings for movement between a retracted position and an extended position. The lock assembly further has a bias member which biases the latch member toward the extended position. The latch member is forced to the retracted position when the catcher is in said open position and is biased to the extended position when the catcher is in the closed position. The biasing to the extended position of the latch member slidably engages the latch member with the latch notch which locks the catcher in the closed position and retains the second coupling pin within the second receiving notch by the obstruction of the jaw.
The present invention includes a coupler assembly mounted on a work machine. The coupler assembly includes a cylindrical catcher rotatably mounted between a pair of plates. During coupling, the catcher is rotated at a cam surface by an implement coupling pin which allows a lock member mounted to the pair of plates to slidingly engage automatically with the catcher for locking the catcher in a closed position. The closed position establishes that a jaw of the catcher is located in a position which retains the implement coupling pin within a receiving notch of the catcher thereby coupling the implement to the work machine. The ability to couple an implement to a work machine with ease and simplicity in conjunction with the utilization of durable components, increases usability and reliability while reducing costs.